A child being carried in a child restraint seat can be subjected to relatively high impact forces upon deployment of an air bag against the child, whether that air bag is a front air bag or a side curtain air bag. Accordingly, it is suggested that children beneath a selected size and weight not be subjected to impact by air bags. In some vehicles, manual switches are provided to deactivate air bag deployment systems when a child restraint seat is occupied by a child. A driver or passenger can forget to operate the manual switch when a child is seated, or the air bag can be left in a deactivated mode when an adult is seated.
This has led to arrangements for automatically deactivating air bags when the presence of a child rather than an adult in a vehicular seat is detected. Currently, these devices respond to the weight of a person occupying a front passenger seat, whether that person is an adult or a child, rather than responding to the mere presence of a child restraint seat. It has been found that some weight based suppression systems that are installed in the seat cushion of the right front passenger seats have difficulty correctly classifying “Lower Anchorage and Tether for Children” (LATCH) child restraint seats that are attached to the lower anchorages of the front passenger set. The reason for this difficulty is the inability of the suppression system to detect the amount of load being applied by the attached child restraint seat to the set cushion, which results in added weight measurement to the suppression system. This misclassification occurs when this added weight equals the amount of weight that an adult occupant would apply while seated in the right front passenger seat. It is not currently realized that the mere presence of a child restraint seat in almost all cases precludes occupancy of the passenger seat by an adult, who is less likely to experience ill effects from an air bag impact than an infant or small child. Accordingly, there is a need in systems, such as LATCH child restraint seat systems, for detection devices which recognize the mere presence of a child restraint seat and use that recognition to deactivate or alter deployment speeds of airbags.